In semiconductor manufacturing processes, photolithography techniques are commonly adopted to define structures. Typically, an integrated circuit layout is designed and outputted onto one or more photomasks. The integrated circuit layout is transferred from the photomasks to a mask layer to form a mask pattern, and then transferred from the mask pattern to a target layer. However, with the advancing miniaturization and integration requirements of semiconductor devices, including memory devices such as dynamic random access memories (DRAMs), flash memories, static random access memories (SRAMs), and ferroelectric (FE) memories, the semiconductor structures and features of such devices become more miniaturized as well. Accordingly, the continual reduction in semiconductor structure and feature sizes places ever-greater demands on the techniques used to form the structures and features.
For example, to form active regions in the substrate, a plurality of trenches are formed by etching the substrate, and a plurality of island structures, which are used to form the active regions, are obtained and separated from each other by the trenches. Insulating materials are then deposited to fill the trenches and to form a plurality of isolation structures to define and provide electrical isolation between the island structures. However, it is often found that the island structures may collapse due to stress from the insulating material filled therebetween. Consequently, reliability and performance of a device that includes an island structure and an active region are reduced.
This Discussion of the Background section is for background information only. The statements in this Discussion of the Background are not an admission that the subject matter disclosed in this section constitutes a prior art to the present disclosure, and no part of this section may be used as an admission that any part of this application, including this Discussion of the Background section, constitutes prior art to the present disclosure.